Locating device

Abstract

A device and method are described for navigating and positioning a central venous catheter into the venous system using two different modes of location. For example, a peripherally inserted central catheter (“PICC”) may be navigated and positioned within the superior vena cava. A light emitting element is used in the first mode to navigate the PICC to the superior vena cava. To improve visibility during navigation, the light emitted from the light emitting element may include a narrow range of wavelengths that generally matches the wavelengths of light that are transmissable through a light absorbing material defining the wall of the catheter. A conductive medium is used in the second mode to monitor an ECG signal in order to position the PICC in the superior vena cava. One advantage of this procedure is that X-ray visualization can be eliminated to reduce the danger associated with X-rays.

The invention claimed is: 
     
       1. A method of locating a central venous catheter within a venous system of a patient, wherein the venous system includes a superior vena cava, the method comprising the following steps:
 extending a locating device and a conductive medium from an access site through one or more lumens of the central venous catheter while emitting light from a location adjacent a distal end thereof bright enough to shine through body tissue from the venous system to the patient's skin, to make the location visible to a naked human eye from outside of the patient, and to navigate the locating device through the venous system by viewing the light through the body tissue by a human eye; 
 establishing access to a vein within an arm or neck of the patient; directing light radially away from the distal end of the locating device; 
 navigating the central venous catheter through the venous system of the patient until the distal end reaches a location within 15 cm of the superior vena cava by viewing the light from outside of the patient through the body tissue, wherein the central venous catheter comprises a distal portion with a tubular wall defining a lumen extending therethrough, the tubular wall being at least partially translucent and defined by a first range of visible light wavelengths and a second range of visible light wavelengths the first range of visible light wavelengths comprising less than 50% of the entire visible light spectrum and the second range of visible light wavelengths comprising more than 50% of the entire visible light spectrum, the first range being at least partially transmitted through the tubular wall, and the tubular wall blocks transmission of all visible light wavelengths within the second range, wherein the first range appears as a color of red, orange, yellow, green, blue, violet or a mixture thereof when a white light is transmitted through the tubular wall; wherein the locating device extends through the lumen of the catheter with an optical fiber having a distal end disposed along a distal portion thereof, the optical fiber being disposed within the lumen and directing the light toward the tubular wall; wherein a light source is in communication with the optical fiber, at least 60% of light output by the light source being within the first range of visible light wavelengths and no more than 30% of the light output being within the second range of visible light wavelengths, wherein the light output is directed through the tubular wall, the light output being visible from an exterior of the patient through the tubular wall and overlying tissues of the patient for navigation through the venous system; and 
 positioning the distal portion of the central venous catheter within the superior vena cava by monitoring an Electrocardiography (ECG) reading through the conductive medium. 
 
     
     
       2. The method according to  claim 1 , wherein the locating device comprises an optical fiber extending from the proximal portion of the locating device to the distal portion of the locating device, a redirection element disposed along the optical fiber, the redirection element directing light passing axially through the optical fiber radially away from the optical fiber while navigating the locating device toward the superior vena cava, and a light source connected to a proximal end of the optical fiber. 
     
     
       3. The method according to  claim 2 , wherein the redirection element comprises a partially or completely removed length of a cladding layer of the optical fiber. 
     
     
       4. The method according to  claim 2 , wherein a distal end of the optical fiber is adjacent the distal end of the central venous catheter. 
     
     
       5. The method according to  claim 2 , further comprising an adapter connected to the light source and a proximal hub connected to the optical fiber, the proximal hub and the adapter being adapted to couple the light source and the optical fiber together for the transmission of light from the light source to the optical fiber, the proximal hub comprising a flexible arm engaging a tapered portion of the adapter, wherein pressure from the flexible arm against the tapered portion pulls the proximal hub into the adapter until a proximal end of the optical fiber is flush with a lens of the light source. 
     
     
       6. The method according to  claim 1 , wherein the locating device comprises an electric supply line adapted to extend from the proximal portion of the locating device to the distal portion of the locating device, a light source connected to a distal end of the electric supply line and adapted to direct light radially away from the locating device, and a power supply connected to a proximal end of the electric supply line. 
     
     
       7. The method according to  claim 6 , wherein the conductive member comprises a coiled wire wrapped around an outer circumference of a length of the locating device. 
     
     
       8. The method according to  claim 1 , wherein the conductive member wraps around an outer circumference of a length of the proximal portion of the locating device, the conductive member thereby being exposed proximally from the proximal portion of the central venous catheter, and the conductive member being connectable to an ECG machine with a clip contacting the outer circumference. 
     
     
       9. The method according to  claim 1 , wherein the conductive member extends axially through one of the lumens of the central venous catheter less than half of an overall length of the central venous catheter. 
     
     
       10. The method according to  claim 1 , wherein the conductive member extends axially through one of the lumens of the central venous catheter along an entire length of the central venous catheter. 
     
     
       11. The method according to  claim 1 , wherein the locating device extends through a valve to extend through the lumen of the central venous catheter, the valve longitudinally retaining the central venous catheter and the locating device together during navigation and positioning of the central venous catheter. 
     
     
       12. The method according to  claim 1 , further comprising a proximal member housing a light source or a power supply, a sterile barrier surrounding the proximal member, and a proximal end of the locating device comprises a conical surface configured to penetrate the sterile barrier to connect the locating device to the proximal member. 
     
     
       13. The method according to  claim 1 , further comprising an ECG extension cable comprising a clip at one end adapted to connect to the conductive member and an ECG electrode snap at another end adapted to connect to an ECG lead. 
     
     
       14. The method according to  claim 1 , further comprising an ECG electrode snap fixedly attached to the conductive member along a proximal portion of the conductive member. 
     
     
       15. The method according to  claim 13 , wherein the ECG electrode snap is disposed more than 300 mm from the access site when the distal portion of the conductive member is within the venous system. 
     
     
       16. The method according to  claim 1 , further comprising a proximal member housing a light source or a power supply connected to a proximal end of the locating device, the proximal member being disposed more than 150 mm from the access site when the distal portion of the locating device is within the venous system. 
     
     
       17. The method according to  claim 1 , wherein the locating device and the conductive member are bonded together to restrain longitudinal movement between the locating device and the conductive member. 
     
     
       18. The method according to  claim 1 , wherein the locating device is disposed coaxially within the conductive member.